Which process occurs without transferring heat or mass to the surroundings?

The correct choice highlights a process known as an adiabatic process, which is characterized by the absence of heat exchange between the system and its surroundings. In such a process, the system is insulated so that no heat flows in or out.

During an adiabatic process, any change in the internal energy of the system is solely due to work done on or by the system. For instance, when a gas is compressed adiabatically, its internal energy increases due to the work done on it, which results in an increase in temperature. Conversely, when it expands adiabatically, it does work on the surroundings, resulting in a decrease in internal energy and thus a drop in temperature.

The distinction of the adiabatic process lies in the fact that while it can involve changes in temperature and pressure during the transformation, these changes occur without any heat transfer. This is different from other processes listed, such as isothermal, isobaric, and isochoric processes, where heat or pressure interactions with the surroundings play crucial roles.